Remove the hacky semaphore override for libhipcxx

[jamesETsmith]

🔨Work Item

There was a change to how libhipcxx last year that explicitly disallows use of semaphore (see my issue ROCm/libhipcxx#10). Since we want to work with the latest version of libhipcxx, we're forced to do some very hacky and brittle things when installing dependencies for graphbolt, see the discussion here: #16.

https://github.com/ROCm/dgl/blob/7da392ad2338694b66ba80ccf975c9a75f1c3f08/script/install_graphbolt_deps.sh#L22-L33

We'd like to get rid of this as soon as possible.